Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0018799 (heart disease)
 34,133 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Abnormal biosynthesis of thromboxane and prostacyclin has been implicated in patients with primary pulmonary hypertension and secondary pulmonary hypertension associated with congenital heart disease, and could be involved in the pathogenesis of pulmonary vascular disease. The chronic effects of an oral prostacyclin analogue, beraprost sodium, on thromboxane and prostacyclin biosynthesis and on pulmonary circulation were investigated in 15 children with pulmonary hypertension. The plasma concentrations of thromboxane B2 and 6-keto-prostaglandin F1 alpha were measured, as was the urinary excretion of 11-dehydro-thromboxane B2 and 2,3-dinor-6-keto-prostaglandin F1 alpha, which are stable metabolites of thromboxane A2 and prostacyclin, respectively. In patients with pulmonary hypertension, the plasma concentration of thromboxane B2 and the ratio of thromboxane B2 to 6-keto-prostaglandin F1 alpha were greater than in healthy controls: 210 +/- 49 versus 28 +/- 4 pg/mL (P < 0.05) and 32.6 +/- 8.9 versus 5.7 +/- 1.8 (P < 0.01), respectively. After 3 months of administration of beraprost, the plasma concentration of thromboxane B2 and the ratio of thromboxane B2 to 6-keto-prostaglandin F1 alpha were reduced significantly: 210 +/- 49 to 98 +/- 26 pg/mL (P < 0.01) and 32.6 +/- 8.9 to 18.0 +/- 6.7 (P < 0.05), respectively. In contrast, the plasma concentrations of 6-keto-prostaglandin F1 alpha in patients were slightly but not significantly higher than in controls, and did not change significantly after administration of beraprost. The concentrations of 11-dehydro-thromboxane B2 and 2,3-dinor-6-keto-prostaglandin F1 alpha in urine correlated significantly with thromboxane B2 and 6-keto-prostaglandin F1 alpha, respectively, in plasma. Beraprost improved the imbalance of thromboxane and prostacyclin biosynthesis and has a potential efficacy for preventing the progressive development of pathological changes in pulmonary vasculature.
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PMID:Chronic effects of oral prostacyclin analogue on thromboxane A2 and prostacyclin metabolites in pulmonary hypertension. 958 94

Aspirin is used to prevent thromboembolism in children with heart disease without evidence supporting its efficacy. Studies in adults report a 5%-51% prevalence of aspirin resistance, yet the mechanisms involved are poorly understood. Our aims were to determine its prevalence in these children and to explore its possible mechanisms. One hundred twenty-three cardiac patients routinely receiving aspirin were prospectively enrolled. Platelet function was measured by Platelet Function Analyzer (PFA)-100 using epinephrine and adenosine diphosphate (ADP) agonists. Aspirin resistance was defined as failure to prolong the epinephrine closure time following aspirin administration. Urine levels of 11-dehydro-thromboxane B(2) (11-dTXB(2)) were measured to determine inhibition of the cyclo-oxygenase pathway. The prevalence of aspirin resistance was 26%. Median ADP closure time was shorter for aspirin-resistant (79.60-115 s) than for aspirin-sensitive (100.60-240 s) patients (p < 0.01). 11-dTXB(2) levels did not correlate with aspirin resistance. Aspirin-resistant patients had higher 11-dTXB(2) levels before (7297 vs. 4160 pg/mg creatinine; p < 0.01) and after (2153 vs. 1412 pg/mg; p = 0.03) aspirin, with a similar percentage decrease in thromboxane (70.5% vs. 66.1%; p = 0.43). Our findings suggest that resistance is not entirely due to lack of inhibition of platelet thromboxane production. Alternative sources of thromboxane and thromboxane-independent mechanisms, such as ADP-induced platelet activation, may contribute to aspirin resistance.
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PMID:Aspirin resistance in children with heart disease at risk for thromboembolism: prevalence and possible mechanisms. 1789 27